The head and stem are designed to nuzzle against the prostate. The curves of the stem provide stimulation up and down the anal canal, a surprisingly erogenous area. The head applies the proper amount of pressure on the prostate for an effective prostate massage. The force of this pressure is controlled only by the man's anal-sphincter and PC muscle contractions, never by his hands.

The perineum tab provides an external prostate massage by pressing against the perineum, and acts as a pivot point to drive the massaging action of the Aneros inside the rectum. A man experiences both an internal and external prostate massage simultaneously. The continuous stimulation of the prostate and perineum leads to stronger orgasms and possibly the Super-O as well.

The handle (all models but the Progasm) is used only to insert and remove the Aneros. (The company warns to not manipulate the Aneros with your hand — it is counter-productive and could be dangerous or injurious to do so.)

The kundalini tab (Progasm only) massages the "kundalini" spot, an accupressure point between the buttocks.

The Evi is made from a rigid body and coated in velvet-touch silicone.

The action of the device upon insertion is highly pleasurable for the user. Many users also report in the blogs at the official site enhanced orgasm through the use of this device.

The device may have no recognized or approved medical use, but was developed and is still marketed under another name by High Island Health as a medical prostate massager. The Aneros site history relates that they had received reports on a gratifying side effect of their device and re marketed it.